The method of extracting hydrocarbons from a shale gas deposit and a device for extracting hydrocarbons from a shale gas deposit

ABSTRACT

A device and method of extracting gas from the gas shale deposit by the partial combustion of hydrocarbons in the deposit in air is described. The method and device uses a gas extraction process and a pyrolysis process. The amount of air is controlled during the pyrolysis process to manage the process and to discharge effluent from the deposit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority as a nationalization of PCT application PCT/PL2015/000185, with an international filing date of Dec. 11, 2015, which in turn claimed priority to Polish Patent application serial number P.410121, filed on Dec. 11, 2014. The contents of each application are hereby incorporated by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The object of the invention is a method of extracting hydrocarbons from a shale gas deposit and a device for extracting hydrocarbons from a shale gas deposit involving the supply of air to the deposit, heating the deposit in order to bring about the effect of pyrolysis, and then the extraction of the results of the partial combustion to the surface of the earth by using one transporting channel.

2. Background of the Invention

Shale gas deposits constitute a type of stones inside which there are small reservoirs of natural gas and moreover there are small reservoirs of liquid natural gas between shale stones. There are molecules of oxygen constituting approximately 2% of the weight of the shale gas stones and there is also solid kerogen inside shale gas stones.

The methods of direct acquisition of hydrocarbons or natural gas from underground deposits known from the state of technology usually comprise the method of hydraulic high pressure crushing of rocks by introducing a mixture of chemicals to the deposit causing the emergence of microslits through which the natural gas present in shale stones is discharged.

The inconvenience of this method are considerable costs of used chemicals, incompetent utilization of kerogen in the solid state found in shale stones, adverse impact of the chemicals on the environment as well as the fear that chemicals will spill without control over this process (because of high pressure used) and that natural gas will be released to the surface which may lead to the contamination of the environment. According to various data, this method uses only 5 to 25% of hydrocarbons found in the shale gas deposit. The proposed method uses the process of pyrolysis of kerogen as a result of which kerogen changes into light hydrocarbons, liquid synthetic oil and ash. The weight of the liquid synthetic oil obtained in the process of pyrolysis reaches 22% of the weight of gas shale. If we assume that the average density of the shale is equivalent to the density of water and the average thickness of the layers of shale gas deposit is, for example, 45 meters and that shale rocks constitute 90% of the weight of the shale gas deposit, the weight of only synthetic oil found in such a layer with an area of one square kilometer is approximately nine million tons.

Polish patent No. PL 222362 discloses a method of obtaining hydrocarbons from the underground deposits, by partial combustion of hydrocarbons within a deposit while adjusting the amount of air supplied to the deposit, through the use of a unit for obtaining hydrocarbons from subterranean deposits formed by performing a primary and side corridors in the deposit, provided with pipes with the valves, one of which running along the transporting shaft is equipped with the ignition device and is used to supply the ignition material and air from the surface of the earth to the deposit, the second pipe running along the transporting shaft is used to discharge gaseous products from the area of the deposit to the surface of the earth and the third pipe is used for discharging liquid products from the deposit to the transporting shaft.

Another solution presented in U.S. Pat. No. 3,024,097 relates to a process and arrangement of apparatus for the production of mixtures of carbon oxides and hydrogen for controlled combustion of carbonaceous fuels underground. The process requires a suitable synthesis catalyst such as sintered iron. The method for the production of the mixture of carbon oxides and hydrogen requires three pipelines. The first as an outer conduit or casing about 200 feet long through which combustion products are removed. The second is tubing, used to supply oxygen or air mounted substantially concentrically in the casing. The third one is a conduit for the introduction of hydrogen.

One more U.S. Pat. No. 4,498,537 relates to a method for the cyclic thermal stimulation of heavy oil adjacent to producing wells to increase recovery of the oil produced therefrom by using an in situ combustion process wherein pure oxygen or a fluid containing a minimum of about 75% by volume pure oxygen is injected into the well as the oxidizing medium, igniting the oil in the reservoir around the producing well so as to produce a combustion zone and to generate combustion gases consisting essentially of carbon dioxide and water in the form of steam, continuing injection of the oxygen until the combustion zone has propagated radially to a distance of about 5 to 50 feet from the producing well, and thereafter recovering oil from the well. The increased temperature, pressure, and the dissolution of the CO2 in the reservoir oil are reducing its viscosity and thereby increase oil production from the well.

SUMMARY OF THE INVENTION

In accordance with the solution, the oil deposit is penetrated by a production well on the entire thickness of the deposit. The production well has perforations on the entire thickness of the deposit. On the surface of the earth there is a cryogenic unit which generates pure liquid oxygen from the air taken in, which air is transported using a cryogenic pump through a pipe to the heat exchanger, where oxygen is vaporized and then the vaporized pure oxygen is subjected to moistening with steam and under the given pressure the mixture of gases is introduced to the oil reservoir where there is self-ignition of the oil from the supplied oxygen or the ignition is carried out with another igniting device. The combustion of the reservoir is sustained in order to raise the temperature of the deposit as well as the saturation of the oil deposit with the carbon dioxide. Both the increase in the temperature and the molecules of carbon dioxide permeating to the reservoir of the oil reduce the viscosity of the oil and additionally the rise in the temperature increases the pressure of the gasses in the deposit. These three factors facilitate the outflow of the oil to the surface of the earth after the combustion process of the deposit is stopped. In this solution the surface of the earth is connected with the oil deposit using two pipes.

The aim of this solution in accordance with this invention is to provide a solution that allows the extraction of hydrocarbons from the underground shale gas deposit enabling the extraction of hydrocarbons to the surface irrespective of whether they are in solid, liquid or gaseous state.

The method of extracting hydrocarbons in accordance with the invention to the surface of the earth is achieved through the utilization of only one transporting channel.

The method of extracting liquid and gaseous hydrocarbons from the shale gas deposit by the partial combustion of hydrocarbons in the deposit itself with the supply of the appropriate quantity of air is characterized in that it involves the process in which flammable material is provided to the deposit, this flammable material is lit up, resulting in the ignition of the shale gas deposit. After ignition of the shale gas deposit the process of controlling the speed of the partial combustion of the deposit through the adjustment of the quantity of the air supplied to the deposit is started in order to guarantee the optimum utilization of the hydrocarbons in the deposit. In the process of pyrolysis light hydrocarbons, synthetic oil and ash (as waste) are produced.

The surface of the earth is connected with the deposit by the channel designed to supply materials igniting the deposit, to supply the air and to discharge the mixture of gasses created in the processes of evaporation and pyrolysis and to discharge the mixture of synthetic oil with ash created in the process of pyrolysis of underground hydrocarbons.

The aim of extracting hydrocarbons from underground is achieved by using one transporting shaft or pipeline, connecting the surface of the earth with the shale gas deposit.

The utilization of the transporting shaft is necessary when liquid and gaseous hydrocarbons are extracted from shale gas deposits situated at greater depths.

The amount of air used to support partial combustion of hydrocarbons in a shale gas deposit supplied to the pipeline and the amount of gas discharged from the shale gas deposit is controlled alternately by means of valves installed on the pipeline or on the outlet from the transporting shaft. The amount of air supplied to the deposit during the partial combustion of hydrocarbons in a shale gas deposit is adjusted so as to ensure the conversion of hydrocarbons in the liquid state into gaseous state and hydrocarbons in the solid state into the liquid and the gaseous states.

Increase in gas pressure within the shale gas deposit under partial combustion of hydrocarbons with the closed valve on the pipeline supplying the air to the pipeline or the transporting shaft connecting the surface of the earth with the deposit is used for discharging products of the process from the shale gas deposit.

The advantage of the method of extracting gas from the shale gas deposit and the device for extracting gas from the shale gas deposit, according to the invention, is a significant reduction in capital expenditures, when the channel in the form of a pipeline or a transporting shaft connecting the shale gas deposit with the surface of the earth is used.

The object of the invention in the version using only a pipeline as a channel linking the shale gas deposit with the installation controlling the extraction process made on the surface of the earth is presented in the FIGURE in which the device for extracting gas from the shale gas deposit is presented to be carried out diagrammatically in the form of a cross section of the transporting shaft constituting a kind of pipeline.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and advantages described above are achieved by the flaring device that is the subject of the invention, which is described here below with reference to the attached drawings, wherein:

FIG. 1 shows an overview of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings.

As used herein, an element step recited in the singular and preceded with the word “a” or “an” should be understood as not excluding plural said elements or steps, unless such exclusion is explicitly stated. Furthermore, the references to “one embodiment” of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property.

According to the method the process of extracting gas from the shale gas deposit starts with the opening of an air-tight hatch 9 through which a combustible material is provided to the pipeline 3 and the combustible material is lit up. The pipeline 3 is in its upper part closed with a permanent forefoot 10. After ignition of the gas in the shale gas deposit 2 which is found between the waste rocks, the air-tight hatch 9 is closed with an air-tight cover 8. With the hatch 9 closed, the pressure gauge 7 closed and the valve 5 opened, the air is pumped into the pipeline 3 through the pipe 4 in order to support partial combustion in the shale gas deposit 2. Then the valve 5 is closed. After the valve 5 has been closed the process of partial combustion of the deposit 2 is continued with the simultaneous increase in the gas pressure within the deposit 2. After the gas pressure within the deposit 2 is experimentally selected, the pressure gauge 7 is opened and the released gas is discharged to the surface through the pipe 6. The pressure gauge 7 remains open until the pressure inside the deposit reaches a value slightly exceeding the atmospheric pressure, then the pressure gauge 7 is closed.

Then the next cycle of extracting the gas is starting from the opening of valve 5 and the supply of the next portion of the air in order to sustain partial combustion. Favorably the pipeline 3 is equipped with openings 13 enabling the combustion of hydrocarbons in the shale gas deposit 2 and the supply of the air through pipe 4 to the shale gas deposit 2.

The device for extracting hydrocarbons from the shale gas deposit in the form of a pipeline, according to the invention, is composed of a pipeline 3 equipped in an air-tight hatch 9 with an air-tight cover 8, through which flammable material is supplied for the purposes of combustion of hydrocarbons in the shale gas deposit 2, with a pipe 4 supplying the air under increased pressure having a valve 5 regulating the amount and pressure of the supplied air, with a pipe 6 discharging the liquid and gaseous products obtained as a result of combustion of hydrocarbons from the shale gas deposit 2 equipped with a pressure gauge valve 7, pipeline 3 within the area of the shale gas deposit 2, has openings 13 enabling the combustion of hydrocarbons in the shale gas deposit 2 and the supply of the air through pipe 4 to the shale gas deposit 2 and the products of partial combustion of the deposit 2 are discharged through these openings, and further through the pipeline 3 and along pipe 6 with a pressure gauge valve 7.

In one embodiment, the system comprises a method of extracting gas from the gas shale deposit by the partial combustion of hydrocarbons in the deposit in air, characterized in that the gas extraction process is carried out with the use of a pipeline 3 through which a flammable material is provided, it is lit up, resulting in the ignition of the gas shale deposit 2, and then the process of controlling the amount of air, used for the partial combustion of hydrocarbons in a shale gas deposit, and for discharging gas from the gas shale deposit 2 to the surface of the earth the pipeline 3 is used or the supply shaft, the amount of air supplied through the pipeline 3 or through the supply shaft to the gas shale deposit 2 being adjusted so as to ensure the conversion of hydrocarbons in the solid state into the liquid and gaseous state through the process of pyrolysis and hydrocarbons in the liquid into a gaseous state.

The method may be characterized in that the amount of air used to support partial combustion of hydrocarbons in a gas shale deposit to the pipeline 3 or to the supply shaft and the amount of gas discharged from the shale gas deposit 2 is controlled alternatively by means of the valves 5 installed on the pipe 4 and the valve 7 installed on the pipeline 5.

Alternatively, the system comprises a device for extracting gas from the gas shale deposit in the form of a pipeline characterized by that it has the a form of the pipeline 3 with upper air-tight cover 10 mounted to pipeline 3 equipped with an air-tight hatch 9 and with an air-tight cover 8, through which a combustible material is provided is provided to start partial burning of hydrocarbons within the gas shale deposit 2, with the pipe 4 supplying air with increased pressure equipped with a valve 5 controlling the pressure and amount of air supplied, with the pipeline 6 discharging gases from the shale gas deposit 2 resulting from the partial combustion of hydrocarbons equipped with a pressure gauge valve 7 and with the openings 13 for the partial combustion of hydrocarbons within a shale gas deposit and discharging gases from the shale gas deposit 2 through the pipe 6.

The device as described above may be also be characterized by that it has supply shaft instead of pipeline 3.

In summary, the system comprises a method of extracting gas from the gas shale deposit by the partial combustion of hydrocarbons in the deposit in air, characterized in that the gas extraction process is carried out with the use of a pipeline 3 through which a flammable material is provided, it is lit up, resulting in the ignition of the gas shale deposit 2, and then the process of controlling the amount of air, used for the partial combustion of hydrocarbons in a shale gas deposit, and for discharging gas from the gas shale deposit 2 to the surface of the earth or the supply shaft, supplied to the pipeline 3, begins, the amount of air supplied through the pipeline 3 to the gas shale deposit 2 being adjusted so as to ensure the conversion of hydrocarbons in the solid state into the liquid and gaseous state, and hydrocarbons in the liquid state into a gaseous state. 

1.-4. (canceled)
 5. A method of extracting hydrocarbons from a shale gas deposit involving the supply of air to the deposit, then igniting the deposit in order to bring about the effect of pyrolysis through partial combustion of hydrocarbons and then extracting the gas to the surface of the earth, comprising: a process of supplying flammable materials and air to the shale gas deposit and next discharging products of evaporation and pyrolysis of shale gas deposit is carried out with use of a single transporting conduit, favorably a pipeline or a supply shaft; wherein amount of air supplied through the single transporting conduit to the shale gas deposit is adjusted so as to ensure conversion of hydrocarbons in a liquid state into a gaseous state and hydrocarbons in a solid state into a gaseous and liquid state.
 6. A method according to claim 5, wherein the amount of air supplied through the pipeline or the supply shaft, which air is used to support partial combustion of hydrocarbons and the amount of hydrocarbons discharged from the shale gas deposit by this pipeline is controlled alternately by means of a valve installed on the pipe and a valve installed on the pipe.
 7. A device for extracting hydrocarbons from the shale gas deposit comprising: a pipeline wherein the pipeline has an air-tight permanent forefoot and is equipped with an air-tight hatch, through which a combustible material is provided to start the burning of hydrocarbons within the shale gas deposit, then with the pipe supplying air at increased pressure equipped with a valve controlling the amount and pressure of air supplied, with the pipe discharging the products from the shale gas deposit resulting from the partial combustion of hydrocarbons equipped with a pressure gauge valve, additionally the pipeline, has the openings facilitating the supply of air to the shale gas deposit and facilitating the discharging of the products of partial combustion of the shale gas deposit to the surface of the earth.
 8. A device according to claim 7, wherein the transporting shaft performs the functions of the pipeline. 